Integrate fast_search branch into master

[flamholz]

Will not do this until we have fully tested the AWS instance and are ready to switch the DNS.

Elad -- please verify that you are not relying on the master branch for anything other than equilibrator.weizmann.ac.il before I do this. You can then reassign to me and I'll handle the integration.

[eladnoor]

I confirm that the master branch is not used for anything else.

[flamholz]

This is done.